My Time at Sandrock: Monster Whisperer Review (Smartik1)
You can dispatch up to 10 pets to fetch water at the same time (and repeatedly the same day too). With this, you will never have water problems, ever. You can catch them from day 1,
The shiny pets have a passive ability that should help you when set to follow (e.g. mine with you, salvage with you). They are also a bit bigger than their regular variants. The bonus is randomly generated on capture, but also not meaningful enough to stress over it.
Most of the value comes from dispatch. In combat, they fight too slowly and miss too often to make much of a difference. I suspect you could use them to spend the rest of your day fighting when you are out of energy. They can be set to attack aggressive mobs automatically, otherwise they will attack anything passive that you hit at least once.